Surgical instrument

ABSTRACT

A surgical instrument used in removing plaque from arterial walls to increase the amount of blood flow through the arteries. The instrument comprises an elongated arcuate member having single or double internal cutting edges and an outer curved surface which acts as a safety guide to prevent the cutting edge from cutting deeper than desired. The outer curved surface also causes the blade to follow the curvature of the arterial wall and to hold the blood vessel properly open. When double cutting edges are provided the instrument can be moved back and forth and from side to side for maximum plaque removal efficiency.

lilMlIlS (1348 United States Patent 1 1 Skiff et al. 1 June 3, 1975 [54] SURGICAL INSTRUMENT 3,448,74l 6/1969 Dennis et al 128/304 [76] Inventors: Aphrodite P. Skiff, 5 Darley Rd., Primary Examiner channing L Pace Plamview, NY. 11803, John C. A A St h E F Id Rauth, 22 Winkle Point Dr., Eatons Neck, NY. H768 [57] ABSTRACT [22] Flled: 1973 A surgical instrument used in removing plaque from [2|] Appl. No.2 387,494 arterial walls to increase the amount of blood flow through the arteries. The instrument comprises an [52] us. c1, 128/305; 128/304 f 'fg gg f f zf 2:223 gz 'gif' f f j gztfi g 511 1111. c1; A61!) 17/32; A6lb 17/22 g g [58] new of Search 28/304 305 which acts as a safety gulde to prevent the cutting edge from cutting deeper than desired. The outer curved surface also causes the blade to follow the cur- [56] UN]TE S :;S rENTS vature of the arterial wall and to hold the blood vessel properly open. When double cutting edges are prol,663,76l 3/1923 Johnson.............................. 128/305 vided the instrument can be moved back and forth 2.331.732 10"943 Rylmek 123/304 and from side to side for maximum plaque removal ef- 2,495,794 l/l950 Weller 128/304 X ficiency' 2,730.l0l l/l956 Hoffman l28/305 2,944,552 7/l960 128/304 9 Claims, 8 Drawing Figures PNEPJTED Jun 3 1975 w wE QR 1 SURGICAL INSTRUMENT FIELD OF THE INVENTION This invention relates to instruments used in vascular and renal surgery, especially an instrument for removing plaque and cholesterol from inside arterial walls, that is, to eliminate stenosis and thereby increase the effective open area of the artery to increase blood flow.

BACKGROUND OF THE INVENTION One of the major problems in present day health is the amount of deaths caused by atherosclerosis, that is, the interior walls, or intima, are covered with a plaque deposit which slowly builds up so that it will eventually occlude the artery and thereby prevent blood flow. Plaque varies in consistency from soft to brittle or calcified, and thereby even when a small amount exists, it prevents the normal operation and flexibility of the blood vessel wall. This combination of a lessening in flexibility and resulting blockage causes an excess strain on the heart muscle which can lead to stroke, or other serious problems and possibly death. Thus, the need for instruments which can quickly and efficiently remove this plaque deposit from blood vessel walls is important.

Previously, there have been knives and other sharp instruments which have been inserted into the walls of the blood vessels, especially arteries, to remove plaque deposits. These instruments often created more problems than benefits. The cutting edge was on the top of the instrument without any safety element involved. Therefore, if the tip were moved slightly in error, it would puncture the arterial wall and might lead to complications. Also, very often the instrument was a thin needle-like device, which due to its configuration, was incapable of properly removing all plaque from the arterial wall and would leave behind patches of plaque permitting resumption of increased plaque deposits. Additionally, this narrow configuration would not allow for proper opening up of the artery for plaque removal.

Thus, a plaque-removing instrument is needed which properly prevents the cutting edge of the instrument from puncturing the inside of the arterial walls and which properly holds open the artery during plaque removal.

SUMMARY OF THE INVENTION The object of this invention is to provide a plaqueremoving surgical instrument which has a safety means to prevent the cutting edge from puncturing a blood vessel wall.

Another object of this invention is to provide a cutting edge on the instrument which is longitudinally disposed so as to prevent accidental jamming and puncturing of the blood vessel walls.

Another object is to provide such an instrument which properly keeps the blood vessel open during the cutting operation.

A further object is to provide an instrument which lifts up the plaque to start the operation and then cuts away the plaque to complete the operation.

A further object is to provide a plaque-removal instrument having cutting edges on two longitudinal sides to obtain the maximum cutting effect.

An instrument is provided for removing plaque from the intima of arterial walls. The instrument comprises an arcuate elongated instrument having rounded edges and a rounded forward wall. Protecting means are provided to protect a cutting edge which is longitudinally disposed and set back from the outer edges to prevent accidental cutting of the arterial wall during plaque removal. The instrument can also have a slightly rounded elevator tip which starts the separation procedure of plaque from the intima wall and has two cutting edges which are curved and longitudinally disposed to the rear of the elevator tip. An extended portion behind the cutting edge provides protection to prevent the cutting edges from cutting too deeply.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an overall view of the surgical instrument of this invention.

FIG. 2 is a cross-sectional view taken along lines 2-2 of FIG. 1.

FIG. 3 illustrates the surgical instrument of FIG. I in place in an artery.

FIG. 4 is a cross-sectional view of FIG. 3.

FIG. 5 is a view of another embodiment of this inven tion.

FIG. 6 is a cross-sectional view FIG. 5.

FIG. 7 is a view of the instrument of FIGS. 5 and 6 in place in an artery during the plaque removal operation.

FIG. 8 is an enlarged view of the blade of the instrument of FIG. 5.

PREFERRED EMBODIMENT OF THE INVENTION The instrument comprises a blade section 2 and a handle 4 connected by a thin, cylindrical extending member 3. The blade itself is an integral arcuate member of stainless steel in an arc of approximately including a semicircular front section 8 which prepares the plaque for cutting, a midsection 10 which includes the cutting edges and a rear section II which includes a guide and an attaching means for connecting the blades to the extending member. The front section consists of a leading edge 12 which is rounded in configuration with a slight point 14 at the apex thereof. This forms an elevator tip, that is, a tip which can be placed between the plaque and the arterial wall to lift the plaque from the wall during the start of the plaqueremoval operation.

To facilitate this lifting function there is a slight taper 15 to this edge. In back of this front section is a midsection 10 which includes two cutting edges 32 and 34 which are inwardly convex and extend toward the center of the blade. The edges begin from points 16 and 17 (the widest point of the blade at the end of the from section) and terminate at points 18 and 19. These edges are sharp, being honed to a thin cutting edge as shown more clearly in the cross-sectional view of FIG. 2. The honing is done from the inner surface to the outer surface. If desired, it could be done in reverse from the outer to the inner surface.

The other section of the blade which is in back of this midsection is a rear section 21. This section has two rounded outer edges 23 and 25 which extend outwardly of the instrument of y from the cutting edges and then curve inwardly and terminate in a tab 26. At the maximum width 27, the width of this section is the same as the width of the front section. Tab 26 or other connecting means which is provided at the end of this section attaches the blade to extending member 3.

The blade, as aforementioned, is arcuate in shapeas more clearly shown in FIG. 2. The outer surface and the inner surface 13 have approximately the same center of curvature with the outer surface having a greater radius than the inner surface. The cutting edges 32 and 34 are beveled from the outer surface to the inner surface so that the actual cutting part of the edge does not extend further than the outer surface of the blade. Thus, when the blade is placed in an artery (as will be described in more detail), the outer surface 15 contacts the wall of the artery so that the cutting edges will be kept a distance away from the surface of the wall. It therefore cannot accidentally nick or cut the wall of the artery during the plaque removal operation. Also, because the front and rear sections are wider than the midsection (as shown in FIG. 2), the cutting edges are further protected so that they will not accidentally nick the wall in that manner.

The extending member is an elongated cylindrical supporting member 3 which is of stainless steel tubing or other strong material and is permanently attached to the handle 4. The holder is constructed of nylon or other similar material, and may be any suitable shape which permits for easy grasping and good control. As shown in the illustration of FIG. 1, it consists of a forward section which is conical in shape. 42. The apex of this section has a circular opening into which the extending member 3 is staked. The base of this conical section joins with a hexagonal section 44 which provided a good gripping surface and terminates in a rounded dome-like section 46 so that there are no sharp edges present. The instrument thus consists of a solid grasping handle and a slightly flexible extending member which allows for deeper insertion of the blade into the blood vessel as shown in FIG. 3.

For using the instrument, an incision 45 is made in the artery 43 where the plaque is to be removed. The incision is generally made above the region that is involved. The blade portion of the double-edged instrument is then slowly inserted into the artery and maneuvered until the elevator tip 14 of the instrument is positioned between the plaque 46 and the internal arterial wall 48. The plaque is then lifted slightly from the arterial wall and the instrument moved so that now a cutting edge is inserted between the wall and the plaque. This is the position shown in FIGS. 3 and 4. The instrument is then slowly moved from side to side causing the cutting edges to slowly cut the plaque away from the arterial wall in small sections until the plaque is completely removed from the arterial wall in the section involved. During this cutting operation, the curve 15 of the outer surface of the instrument permits it to closely follow the curve of the arterial wall. As aforementioned, this prevents the instrument from accidentally cutting into the arterial wall.

It is noted that this instrument can be made to various sizes and configurations. For example, the blade from end to end can be about 1.25 inches, while the cutting edge from end to end can be about 0.7 inch, and the length of the cutting edges can be about 0.55 inch. The radius of curvature of blade can also vary depending upon the size of the arterial wall involved. As shown in the drawings, it is about 120 of arc; however, this may vary depending upon the blood vessel involved in the operation.

The instruments can, if desired, be provided in a set of various sizes so as to accommodate different'sized arterial walls. The following table gives examples of inside and outside diameters of curvature of a set of such blades.

It will also be appreciated that the blade can be manufactured to achieve the desired degree of strength and flexibility. It can be hardened if necessary.

Another embodiment of the invention is shown in FIGS. 5-7. This instrument is especially useful after the plaque removal operation has already been started. such as by the instrument of FIGS. 1-4. The instrument comprises a handle 59 similar to the handle of the instrument shown in FIGS. 14. To this handle is connected a long extending member 50 which is cylindrical in shape, and which terminates in the blade member 52. The extending member is the same as the member of the embodiment of FIGS. 1-4. The blade member is arcuate in configuration, as shown in FIG. 6 covering an arc of about 120 and consists of a from section 60, a midsection 62, and a rear section 64. The front sectron has a leading edge 66, which is rounded having curved edges 67 and 68 and is adapted to elevate and lift the plaque away from the arterial walls as previously described with respect to the instrument of FIGS. 1-4. The front section ends in a vertical edge 70 on one side and is continuous edge with edge 72 of the midsection on the other side.

The midsection comprises a longitudinal straight section having a straight non-cutting edge 72, and a straight cutting edge 74, the latter being set back from the outer edge of the blade. The cutting edge is beveled 76 in a similar manner to the cutting edges of the blade of the embodiment of FIGS. 1-4. The cutting edge as shown in FIG. 6 is beveled from the outer surface 77 to the inner surface 79 so that the actual cutting edge is contiguous with the inner surface and does not extend beyond the outer edge. This construction, in the same manner as discussed with respect to the embodiment of FIGS. l-4, protects the cutting edge and ensures that the arterial wall will not be accidentally nicked or cut during the plaque-removal operation.

The rear section 64 is curved in the same manner as the front section. It includes two curved edges 80 and 82, a vertical edge 84 which extends down to the cutting edge and an extending tab 86 for connecting the blade to the extending member. The front and rear sections keep the blade properly positioned and prevent its accidental nicking of an arterial wall. Vertical edges 70 and 84 also act to prevent the cutting edge from nicking the arterial wall during operation.

It is noted that edges 70 and 84 can be rounded (as shown by the dotted lines in FIG. 8) to include cut outs underneath. This configuration is provided with the larger blade sizes to provide a greater cutting edge.

Operation of this embodiment is the same as that of FIGS. 14, except that the initial plaque-lifting function can be done with another instrument, such as the instrument of FIGS. l4. Also, in operation, this instrument is only rotated in one direction instead of being rocked back and forth, since it only has a single cutting edge.

Thus, instruments have been disclosed for plaqueremoval operations which have safety means for preventing the cutting edge from cutting the arterial walls. These instruments can also have means for initiating the plaque separation step and continuing with the cutting and removal of the plaque.

It will be appreciated that while specific embodiments of the present invention have been disclosed, many modifications thereof may be made by one skilled in the art which falls within the true spirit and scope of the invention.

We claim:

1. A surgical instrument for removing plaque from blood vessels comprising a handle having a long tubular member an arcuate blade member describing an arc of less than half a circle connected to said long tubular member and having an outer surface of larger radius and an inner surface of smaller radius, said smaller radius being substantially larger than the diameter of said tubular member, including a distal non-cutting section having a rounded outer edge a proximal non-cutting section a midsection having a cutting edge positioned longitudinally between said distal and proximal sections, said cutting edge being positioned at a radius which does not exceed the radius of the outer surface.

2. The instrument of claim 1 wherein said proximal and said distal sections have arcuate circumferences that are greater than the arcuate circumference of substantially all of said midsection.

3. The instrument of claim 2 wherein the edge of the distal section has a slight point thereto and wherein the cutting edge is curved inwardly.

4. The instrument of claim 3 wherein a second cutting edge which is substantially identical and positioned opposite to the first cutting edge.

5. The instrument of claim 2 wherein a rear edge of said cutting section is a non-cutting edge.

6. The instrument of claim 5 wherein the cutting edge is straight and parallel to the axis of curvature of said inner and outer surfaces.

7. The instrument of claim 6 wherein two tabs extend from the distal and proximal sections of the blade toward each other and in front of the cutting edge.

8. The instrument of claim 7 wherein the distal section has a rounded outer edge.

9. The instrument of claim 4 wherein said proximal section includes a tab to which said long tubular member is connected.

* IF F i 

1. A surgical instrument for removing plaque from blood vessels comprising a handle having a long tubular member an arcuate blade member describing an arc of less than half a circle connected to said long tubular member and having an outer surface of larger radius and an inner surface of smaller radius, said smaller radius being substantially larger than the diameter of said tubular member, including a distal non-cutting section having a rounded outer edge a proximal non-cutting section a midsection having a cutting edge positioned longitudinally between said distal and proximal sections, said cutting edge being positioned at a radius which does not exceed the radius of the outer surface.
 1. A surgical instrument for removing plaque from blood vessels comprising a handle having a long tubular member an arcuate blade member describing an arc of less than half a circle connected to said long tubular member and having an outer surface of larger radius and an inner surface of smaller radius, said smaller radius being substantially larger than the diameter of said tubular member, including a distal non-cutting section having a rounded outer edge a proximal non-cutting section a midsection having a cutting edge positioned longitudinally between said distal and proximal sections, said cutting edge being positioned at a radius which does not exceed the radius of the outer surface.
 2. The instrument of claim 1 wherein said proximal and said distal sections have arcuate circumferences that are greater than the arcuate circumference of substantially all of said midsection.
 3. The instrument of claim 2 wherein the edge of the distal section hAs a slight point thereto and wherein the cutting edge is curved inwardly.
 4. The instrument of claim 3 wherein a second cutting edge which is substantially identical and positioned opposite to the first cutting edge.
 5. The instrument of claim 2 wherein a rear edge of said cutting section is a non-cutting edge.
 6. The instrument of claim 5 wherein the cutting edge is straight and parallel to the axis of curvature of said inner and outer surfaces.
 7. The instrument of claim 6 wherein two tabs extend from the distal and proximal sections of the blade toward each other and in front of the cutting edge.
 8. The instrument of claim 7 wherein the distal section has a rounded outer edge. 